GPS accuracy wo approximations #1034
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… GPS_RAW_INT if on mavlink v2.0, or on DOP values otherwise.
| fix->position_covariance[6 + 2] = std::pow(2 * hdop, 2); | ||
| // With FCU protocol v2.0 use accuracies reported by sensor | ||
| if (UAS_FCU(m_uas)->get_protocol_version() == mavconn::Protocol::V20 && | ||
| raw_gps.h_acc > 0 && raw_gps.v_acc > 0) { |
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That is ok, but i think that bit faster: msg->magic == MAVLINK_STX.
MAVLINK_STX= 0xfd (v2.0)MAVLINK_STX_MAVLINK1= 0xfe (v1.0)
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Also that check is not depend on link configuration, because it always can receive v1 and v2 msgs.
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Hmm, perhaps it is good idea to add is_mavlink_v10 and is_mavlink_v20() inline helpers...
Will add that after merge.
| raw_gps.h_acc > 0 && raw_gps.v_acc > 0) { | ||
| fix->position_covariance[0 + 0] = fix->position_covariance[3 + 1] = std::pow(raw_gps.h_acc / 1E3, 2); | ||
| fix->position_covariance[6 + 2] = std::pow(raw_gps.v_acc / 1E3, 2); | ||
| fix->position_covariance_type = sensor_msgs::NavSatFix::COVARIANCE_TYPE_DIAGONAL_KNOWN; |
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About filling cov matrix, i'd like to see Eigen::Map here (ftf::EigenMapCovariance3d), old code done long before we start to use Eigen.
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Pseudocode:
ftf::EigenMapCovariance3d cov(fix->position_covariance.data());
xy = pow(...);
cov.diagonal() << xy, xy, z;
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Updated according to review. |
| fix->position_covariance[6 + 2] = std::pow(2 * hdop, 2); | ||
| // With FCU protocol v2.0 use accuracies reported by sensor | ||
| if (UAS_FCU(m_uas)->get_protocol_version() == mavconn::Protocol::V20 && | ||
| raw_gps.h_acc > 0 && raw_gps.v_acc > 0) { |
There was a problem hiding this comment.
Hmm, perhaps it is good idea to add is_mavlink_v10 and is_mavlink_v20() inline helpers...
Will add that after merge.
GPS accuracy published by mavros is now based on accuracies reported by FCU in
GPS_RAW_INTmessage if using mavlink v2.0. Otherwise they are approximated by HDOP & VDOP values, scaled by GPS User Equivalent Range Error (UERE) measured in meters.According to #1020.